Tuesday, July 19, 2011

There are many, many different species of Sand Dollar. In fact, these interesting invertebrates have an entire order to themselves! Sand Dollars typically measure only a few inches in diameter, and come in all different colors, depending on the species.

Sand Dollars can be found in oceans around the world. Though you will often find them on beaches, they actually live out in coastal waters. The specimens that you pick up are skeletons of dead sand Dollars that have washed ashore.

Though we think of Sand Dollars as smooth white disks, in life they can actually be quite prickly looking! They have a skin of tiny spines that helps them to burrow and move. They also have tube feet on both the top and bottom, and, like all Echinoderms, they display radial symmetry.

The Sand Dollar has its mouth on the underside of its body. They use their tube feet to sift through the side and direct their tiny meals into the mouth part.